This article was #17 in PDmag's Top 25 most-well read articles in 2011. Click here to jump to the article.

Summary: Since genomics testing officially began in January of 2009, it has developed a wider application in the dairy industry. During a producer roundtable discussion, held by Alta Genetics in January 2011, Nate Zwald explained how genomics testing their herds can ultimately improve the genetic progress of their operations.

Because this article was so popular, we asked Zwald a follow-up question: 

Q: What factors make it profitable for a herd to genomic test their females?

A: Genomic testing females can be a profitable part of a complete genetic plan, but the investment cost needs to be weighed against the benefit. Here are some points to consider:

1. You have to take action on the results of a genomic test. Without different decisions than you would do otherwise, you have no opportunity to benefit from this testing. Too often I have heard about "introductory testing" which is done, and results received, but nothing was done with them.

2. Strategies for genomic testing cows have not shown to be profitable.

3. There are a number of strategies where genomic testing heifers can be profitable, all which require ranking the heifers in your herd and then working specifically on the top end (through embryo transfer or use of sexed semen) or the bottom end (through culling). Eliminating the bottom end of your heifers works by increasing the genetic average (and therefore future profitability) of the remaining heifers. While producing more offspring from the top ranking heifers in your herd, increases the genetic average of the next generation of your animals.  However with either of these strategies, you must increase the genetic averages by enough to offset the cost of genomic testing.

4. The most discussed way to make genomic testing work on a commercial basis is to work on eliminating the bottom end of your heifer herd. Eliminating the bottom is always a good idea, and in certain cases, genomic testing can be profitably used as an aid in ranking your heifers, so the bottom can be sold. In order for genomic testing to be profitable, the following factors must be considered:

a. You have an ability to sell at least 20 percent of the group of heifers tested. If you can’t cull at least 20 percent of the animals tested, you generally cannot move the average genetics of the remaining animals by enough to offset the cost of the original genomic testing.

b. Other ways to assess future profitability of the heifers do not exist. In other words, if you have 1,000 heifers with an ability to sell 200 of them, there should not be obvious other ways to select those 200 heifers. For example if some of the heifers can be sold because of treatment history, growth problems or fertility issues, these should likely be sold first. We must remember that about 70 percent of milk production is due to environment, and animals with challenged health, growth or repro status likely did not have a favorable environment. In other words, to make genomic testing profitable, you need to be able to cull 20 percent of your heifers based on their genetics.

c. You have missing identification on some heifers (lack of Sire ID and/or MGS ID). If you have complete information on SID and MGSID, you can rank your animals based on their pedigree averages. While this ranking is not as accurate as a genomic test, this should be done as a first step, as the only cost for this is time.

d. You have inaccurate identification in your herd. Without accurate Sire ID and MGSID, the ranking you create on pedigree averages will obviously not be accurate.  The average mis-identification rate in the U.S. is about 25 percent, so this is a significant problem that many herds are faced with.

e. You have to have a genetic plan to rank your heifers. A plan can be as simple as selection for NM$, but you must make sure that the methodology and weightings in NM$ align with the goals on your dairy or you need to make your own index for selection. Different index weights can make different animals change rank significantly, and different milk payment schemes and management situations can greatly affect the correct genetic plan for a given dairy.

f. You have significant variation in the animals under consideration. The best animals have to be significantly better than the worst animals in the herd if you are going to make a difference in future profitability by culling the bottom animals.

The genetic progress equation is simple:

Selection Intensity X Accuracy X Variation
Generation Interval

Selection Intensity: The proportion of animals selected to be parents of the next generation (generally since all females are bred back to be parents of the next generation on a given farm, the female selection intensity is 0). This can be increased by not breeding/culling the bottom end of your heifers.

Accuracy: This is greatly affected by lack of identification or mis-identification on a parent average basis, and even with complete parentage available, accuracy is significantly increased with genomic testing to levels never before realized on most females.

Variation: This is point ‘e’ above. Your best animals have to be better than your worst, or you can’t make genetic progress.

Generation Interval: When we increase selection intensity, accuracy, and variation, this is compounded if we reduce generation interval by getting more offspring out of younger animals.

A new development in genomic testing is the 7K chip, which is now available. This is replacing the 3K chip and provides more accuracy at a similar price. However it does not significantly change the considerations listed above. But if/when the price of this technology drops significantly, then you do not need to cull 20 percent of your animals to make this investment pay off.

The current cost is about $40/sample, but when this drops to $20 or less, the situation changes drastically. Stay tuned because just like most technologies, the price is almost certain to drop over time, and when it does it will likely be profitable for this technology to be adopted on a much wider basis in commercial dairies.

There are a lot of talented people in the industry from the companies and associations offering genomic testing, and it is important to work with trusted individuals which can help you determine if genomic testing should be implemented as part of your genetic plan.
—Nate Zwald, Senior Manager, Alta Genetics, Wisconsin

[Click here or on the image above right to see the full list of the Top 25 articles of 2011. Click here to see the list from 2010.]

ARTICLE

Twenty-five dairy producers and industry professionals gathered in mid-January to learn about genomics testing and establishing a genetic plan for their herds. The producer roundtable discussion, hosted by Alta Genetics, was held Jan. 17, 2011, in Twin Falls, Idaho.

The first question asked was: “What is genomics?” Other questions involved what benefits the testing provided and how a producer could begin using the new technology on their dairies.

Learn the answers to some of these questions in the video below.

Throughout the evening, Zwald focused on how genomics was changing progeny testing, actually reducing the value of progeny testing, since more and more producers are using semen from non-daughter proven bulls. However, Zwald did mention that Alta was still committed to progeny testing their bulls.

Zwald said that genomics officially began in January 2009, and since then, the bulls on the initial genomics list have had daughters enter their proofs. This provided additional data to be incorporated into the system, which provides the opportunity to evaluate the accuracy of the initial rankings. The initial genomic rankings were actually quite stable, but there were some expected shifts among the bulls. With  the past two years of data now added into the system, the young bulls today have a more accurate ranking than those from 2009.

He also explained that the shelf life of a bull is becoming shorter because instead of using lower-tier proven semen, producers are choosing the genetic gain offered by genomic sires. As genomic progress increases, bulls become 'outdated' quicker. He said that the first strike against a bull is if he doesn't have good fertility, the second is lack of calving ease, and finally if a sire genetic prediction changes.

A key discussion point was based around the opportunity for producers to genomic test their own heifers. Zwald said that even at $35-$40 per animal, it is still a substantial investment that needs to be justified. In other words, you must do something with the results that offsets the cost of the test. It was stated that heifers could be ranked genetically even without the use of genomics, so the real advantage of genomic testing is the improved accuracy of the ranking. In order to offset the cost of the testing, producers need to be able to cull the bottom end heifers and have a focused approach for maximizing the number of replacements from the top end through flushing or other technologies.

One of the discussion’s main goals was to inform producers that using genomic-tested bulls was in their best interest, because when combined with a sound breeding plan, it will maximize genetic progress. Choosing to trust genomics and use genomic sires is not enough – producers also need to choose the genetic plan that is right for their operation.

Zwald sorted the main traits producers breed for in their herds into three groups: type traits, production traits and health and longevity traits.

He finished the evening’s discussion by emphasizing that genomics will allow the producer to maximize the amount of progress for the traits that they would like to emphasize in their herds.  PD